Recently, the number of mobile electronic equipments such as cellular phones including gyro sensors has increased. A gyro sensor has been used for a long time in order to achieve detection of the attitude of a mobile electronic equipment or to implement a navigation system. Further, recently, with high functionalization of the mobile electronic equipment, there is a strong demand for use of the gyro sensor to detect the rotational speed or the rotation angle of the mobile electronic equipment so as to implement an application for a game or health management (including detection of a manner of walking)
The mobile electronic equipment often uses the gyro sensor of a type for detecting an angular velocity using a Coriolis force applied to a vibrating object. In such a gyro sensor, a zero-point offset will occur due to temperature change or change with time. Thus, calibration (calibration) is needed. It is because, when the gyro sensor is used without performing the calibration, measurement accuracy of the gyro sensor deteriorates, so that the gyro sensor is not workable.
Patent Literature 1 discloses a technique for transitioning a mobile electronic equipment to a usual power mode during a low power consumption mode of the mobile electronic equipment to execute calibration of a gyro sensor, even if the gyro sensor has not been used for a long time and a zero-point offset has occurred.
Patent Literature 1:
JP Patent Kokai Publication No. JP2010-152587A